A coeporation of dela



I 1,633,149 June 21-, 1927- wlcKs AUTOMATIC TELEPHONE SYSTEM Original Filed July 1921 3 Sheets-Sheet 1 IHI -fiiman urin Mwks June 21, 1927. R 1,633,149

J. WICKS vAU'IK'JMA'IJIC TELEPHONE SYSTEM Original Filed July 6. 1921 IS Sheets-Sheet 2 June 1927'.

J. WICKS AUTOMATIC TELEPHONE SYSTEM Original Filed July s. 1921 I5 Sheets-Sheet 3 Jnhn Mmks Inusn czr' .mumwm MN Patented June 21, 1927.

' I n-i;rsn"sraresi PATENT orries.

JOHN WICK S; -OF OAK PARK, ILLINOIS, ASS IGNOR, BY MESNE ASSIGNMENTS, 'I'O AUTOMATIC'ELEGTRIC INC, OF CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE.

Application filed July 6, 1921, Serial my The present invention relates in general to distance lines eitheras calling or called subscribers. V a

A special objectof the invention is the provision of anew and improved toll service trunking system containing improved circuit arrangements whereby the toll operators can connect with desired calling or called automatic lines which I are equipped with paystations, and whereby such operators can thereafter collect or refund deposited coins as the occasion requires. I

In addition to the above, there are a number oiother improvements not now specifically mentioned which together with the foregoing will be explained hereinafter with reference to the accompanying drawings.

Referring to 'thel drawings, comprising Figs; -1, 2 and 3, there is shown by meansjack J in the "toll switching oflice through the relay group D, which is a form of'repeater associated with the 130k J and its multiples and which is used for translating ground impulses sent by the operators callin; device to ordinarytwo wire impulses, to the transmission repeater E, 'FigflQ, in a main, exchange of thcsystem; the toll first selector F, Fig. 2'; and the toll rotary cons nector H, Fig. The repeater, first selector '26, 1926 I p Strowger switch mechanism is employed, the general'character'oit which is well un- AUTOMATIC TELEPHONE SYSTEM.

482,765. 'Reneweii December 24, 1923.

enable this connector to give rotary service, the test contacts of the fourth to the seventh contact sets inclusive, being those associated with a "group of lines. When it is desired to connect with a line in this group the connec tor l-I will be operated into connection with the first set of contacts; Should the first line be busy the connector will be automatically operated until connection is made with an idle line in the group. If all the lines in the group are busy the connector will not operate but. will maintain itself associatedwith the first set of bank contacts, transmitting a busy signal to .the calling party, and as soon as one of the grouped lines becomes idle the connector will operate to select it. a

'As has; been pointed out hereinbefore, a feature theinvention is the provision of su table arrangements whereby the toll operator can collect or refund coins deposited to pay for a toll connection, and it shouldbe err plaiued that the subscribers stations, or some of them at least, are provided with coin collectinkr devices, or paystationsof the well known type which is described in the U. Sfpatent to Forsbere, No. 1.043219. Paystation equipment of this type is shown diagrammatical y in connection with the substation A, Fig. 3.

In so far as the measured service features of the present case is concerned it'maybe considered as an improvement on the system shown in thetwoprior'applications Serial No. 364,069, Patent No.'1,6l6,402. issued Feb; 1st, 1927, and Serial No. 379.217, (Patent No. 1,586,057, May 25, 1926) filed on March8,-1920, and May 6, 1920, respective-- ly. Inrespect to certain other features of thetoll service trunking system the present system is closely relatedxto the system disclosed in- Patent No. 1,604,372, issued Oct. In view of the fact that the de'rstood, and also because of the descriptions in the publications abovere'ferred to, from which the generalpurposes of the inventi on will be easily appreciated, it will be unnecessary to consider in detail the vari-' o ls switches and other parts of the equipment, and the explanation of the operation of the complete system will at once be proceeded with.

In order to describe the operation of the invention it will be assumed that the sub scriber at substation A desires to obtain a toll connection, and it will be assumed nu ther that tne subscriber has placed the call with the toll recording operator, and that the ticket containing the usual data concerning the desired connection has been forwarded to the toll operator having the cord circuit 0, F 1, for completion.

Having extended the connection to the desired distant exchange over one of her toll li'n@S, SHCl1 for example as the toll line which terminates in the jack J, F 1, and having ordered the-proper local line to be connected up in that exchange, the toll operator will proceed to call the subscriber at substation 31 by. way of the tell service trunking system. Observing that the toll trunk terminating in jack J is idle, as indicated by the normal position ot the visual signal 30, the operator will insert the calling plug P of the cord circuit '0 into the jack J, and will actuate the calling device key K shortly afterwards. Upon the insertion of the plug P into the jack J, a circuit is completed which extends from ground, by way of the springs .29 of the key K sleeve of the plug 1*, sleeve of the jack J, through the resistance Z5 and thence throu h the Windin of the line relay 42 of the repeater D to battery. The line relay 42 is energized over this circuit and, upon operating, completes the circuit of the slow acting relay 45.. Relay 45, upon energizing, prepares a circuit for relay in the repeater D ;at armature 66, and at armature 65 completes the circuit of the visual signals .suchlas 30 land 31 lo- .cated in front of the various toll operators in orderto inform them :thatthe associated toll trunk is now in .use. Then .the line relay 42 energizes, bridge is completed across the trunk conductors 70 and 71 of the outgoing toll service trunk which energizes the .by armature 117, normally closed springs controlled by armature 122, upper left hand winding .01 the repeating C011 3, conductor 70, normally closed springs controlled by armature winding of the polarized relay 44, armature and its front contact, .trunlc conductor 71, lower left hand winding ofthe rcpeating 0011 R, and thence through the 'normally closed springs controlled by armature 123 ground. The line relay 151 of the toll first selector'F, Fig. 2, isenergized over this circuit and, upon operating, completes the circuit of the slow act-ingrelay calling device S in accordance with the telephone number of the subscriber at uost-ation A. hen the calling device dial is operated in accordance with the first digit of the number, a series 01 interruptions 'isproduced in the circuit of the line relay 42 of the repeater D. ".lheline relay 42 deencrgizes a plinality oi times in response to these interruptions, each time opening the previously traced bridge across the trunk conductors and 71 at its armature 53.. In this manner the first series of impulses are repeated to the line relay 1.51 of the toll first selector F. it each retraction of the armature 52 of the line relay 42. an impulse of current is sent to the slow acting relay 40. Upon energizing, relay 40 provides a bridge across the trunk conductors 70 and 71 at its armature 51 which does not include the winding oft the pol, izcd relay 44, and at its .armatu're 50 places a .direct bridge across the above mentioned trunk conductors on the left hand side of the condensers so as to prevent. the discharge from the condensers, due to dialing, being heard by the toll operator. By the removal of the polarized relay 44 from in bridgeot the trunk conductors the impulsing circuitot the line relay 151 of the first selector F is greatly improved.

In the first selector F the circuit of the line relay 151 being opened a plurality of times 3y the operationot the relay 42 in the repeater D the former relay will retract its armature 166 a corresponding number of times, each time sending an impulse of current to the vertical magnetlfiti of the selector F in series with the slow acting relay 153. Magnet 175 operates to raise the switch wipers 183 186, inclusive, step by step until they are placed opposite the level of bank contacts in which are terminated trunk lines leading to the desired group of connector switches. Upon the first oil normal step of the first selector F the oil normal springs are shifted and a circuit is-coin pleted which extends from ground, by way of oil normal spring 171 and its Working contact, throu h resistance 138 and thence through the polarizing winding of theelectro polarized relay 103 to battery. The electro polarized relay 103 does not operate when only its polarizing winding is ener gized'but does so immediately upon the current flowing in the props dhrection in its upper winding. The slow acting relay 153 is energized in series with the vertical magnet and, upon the first vertical step of the switch shaft, completes a circuit which extends from ground on release trunk conductor 176, byway of front contact and armature168, 01f normal spring 170 and its working contact, and through the winding of the stepping relay 154 to battery. Relay 154, upon energizing, establishes a locking circuit for itself at its armature 169, and at ,The rotary magnet operates to rotate the switch wipers intoengagement with the bank contacts associated with the next trunk line in the, selected level and at the same -time opens the locking circuit of the step armature 170 prepares a circuit for the ro tary magnet 180. Shortly aftervthe termination of the vertical movement of the switch, the slow acting relay 158' deenergia'cs and the circuit of the rotary magnet is .com-;

pleted, extending from ground on release trunk conductor 176, by way of normally closed springs'controlled by armature 168, armature 170 and its front contact, and thence through the winding of the rotary magnet 180 to battery. Magnet 180 operates to rotate the switch wipers 188186,'in-

elusive, into engagement with the first set of bank contacts in the'selected level and at the same time opens the locking circuit of the stepping relay 15%1, which deencrgizes, opening thecircuit of the rotary n'ragneawhich 'deene'rgizes also.-

170 andits working contact, and through the winding of the stepping relay 154 to battery. Relay 15 1, upon energizing, es-' tablishes a locking circuit for itself and completes the circuit of therotary magnet.

ping relay 154;,whichdeenergizes, opening .the circuit of the rotary magnet, which deenergizes also. The alternate operation of thcstepping relay 154 and therotarymag-j net 180 will continue untilfan idle trunk f is found, which, we will assume, is the trunk line terminating inthe bank contacts 187'' 190, inclusive. 'When the'switch wipers are rotated into engagement with "this trunk line, there will] be no ground potential present upon the test contact 189 engaged by the test'wipc'r 185 and no circuitwill be completed for the stepping relay 154; As the switching relay 150 is nolongerrshortf ,circuiteclfithe said relay will be energized" over a, circuit which may be traced from ground on release trunk conductor 176, through the winding of relay 150, back contactand armature 179 off normal jllno' 7 h j 170 and its working contact, and thence throi'igh the winding of the stepping relay 154 to battery. It may be mentioned at this point that the relay 150 is of sufliciently high resistance to prevent the energiza tion of the stepping relay 154 in series with it. Relay 150, upon energizing, completes the energizing circuit'of the line relay 201 of the toll connector switch at the armatures 160 and 16 1.- This circuit may be traced from ground, through the lower winding of the line relay 201 of the connector H, by-

way of back contact and armature 2.1.9, nor- 'mally closed springs controlled by armature 239, trunk conductor 194:, bank contact 190, wiper 186, front contact and armature 16 1, armature 13% and its back cont ct, armature 112 and its backcontact, lower right hand winding of the repeating coil R, upper winding of the electro polarized relay 103, back contact and armature 121, upper right hand winding of the repeating coil it, normally closed springs controlled by armature 111, back contact and armature 130, arn'iature 160 and its front contact, front contact and armature 165, wiper-183, back contact 187. trunk conductor 191, normally closed springs controlled by armature 235, armature 215 and its back contact, through resistance 220,'and thence through the upper winding of the line relay 201 to battery. The elect-r0 polarizedrelay 103 in the repeater E is not energized at this time as the current flowing in its upper winding is not in the proper direction. The line relay 201 ofthe connector switch 'H is energized overthis circuit and, upon'operating, com pletes. the circuit of the slow act ng relay 202. Relay 202,upon energizing, prepares the operating circuits of the connector H at armature 225 and at armature 224 completes a circuit for the ring out off relay .208. 5 Re lay 208, upon energiz ng, establishes a lock, ing circuit for itself at armature 256, which may betraced from ground atfthe'transmissionrepeater E, by way of armature 111 and its back contact, armature 161 and. its

front contact, wiper 184, bank contact 188,

trunk conductor 192, armature 256 and its front contact, and thence through the winding of the ring out off relay to battery. Another result of'the energization of relay 208 is" that the ringing circuit, which would normally be operative immediately upon the connector H connecting with the called line,

islopen'ed and, by means of the previously traced locking circuit, placed under the controlofthe toll operator. It willbe noted that the trunk conductor 1931s the release trunk conductor and that it 'has ground placed upon it from the slow actingrelease relay 152 of the tollfirst selector F. It will also be noted that the switchingrelay150- of the selector F, upon energizing, did not open the circuit of the line relay i151 and th'ereforethis relay remains under-the con trol of the line relay 42 of the repeater D. it will be remembered that the previously traced circuit of .the line relay 201 of the connector H includes the armature 165 of the line relay 151.

It will now be apparent how the connector H controlled. l i hen the toll operator opcrates her calling device in accordance with the next digit of, the subscribers number at substation A, a series of interruptions is produced in the circuit of the line relay 12 oi the repeater D and these are in turn peated to the line relay 151 ot the .f qt selector F. At each retraction of its armature 1.65, the circuit oi? the line relay 201 is opened and the impulses are thus sent to the line relay 201 of the connector H in order to control its operation. At each retraction of the armature 221 of the line relay 201, a

circuit completed which extends from ground, by way of back contact one armature 217, armature 221 and its back contact, armature 225 and its front contact, oit normal springs 228 and 221 through the. winding of the vertical magnet and thence through the winding of the acting relay 207 to battery. The above is the circuit over which the first impulse to the vertical. magnetis transmitted. Upon the first vertical step of the switch, the oil? normal. springs are shifted and the remaining vertical magnet impulses traverse a different circuit, which is the same the one prcviouslytraced, except that it includes the oit normal springs 228 and 229, and armature 253 and its front contac relay 207 "being new in an operated position. magnet 262 operates to raise the switch wipors 270-273, inclusive, step'by step until they are placed opposite the level of bank contacts in which 18 located the contact set associated with the line or the substation A. The 'slow' acting relay 20 t; is energized in series with the vertical magnet and main and final digit of the called subscribers number. As before, the line relay Q2 of the repeater D and the line relay 151 of the selector l operate and transmit a'series oi": impulses corresponding to the last digit of the called number to the line relay 201 of the connector H. Relay 201 deenergizes a plurality of times in response to these int'u'ruptions each time sending an impulse o1 curreht over the following circuit: Ground by way ofbacli contact and armature 217, armature 221 and its back contact,-armature 225 and its "front contact, oil normal springs 22S and 229,-armature 253 and its back conthe bank contacts 27 %277 The vertical this relay will be operated.

, itself at armat' tact, back contact and armature 247, through the winding the slow acting relay 296, armature 242 and its back contact, and thence through the winding of the rotary magnet 260 to battery. The rotary magnet operates to rotate the switch wipers 270 273, inclusive, into engagement with the set oi bank contacts associated with the line of the substation A, which, we will assume, are inclusive. The slow acting relay 206 is energized in series with the rotary magnet and operates its an mature 251 to connect the test wiper 271 to the test rela 205.

Assuming that the desired line is idle at the present time, there will be no ground potential present upon the test contact 275 engaged by the test wiper 271 and no circuit will be completed for the test relay 205.

Then, following the deenergization of the slow acting relay 206,,a circuit may be traced extending from ground, by way of -t contact and armature 223, back conand armature 2 15. lower winding of .witchi rmacure 2 I winding of the switchingyrelay 280 of line switch C and thence through the winding of the motor magnet 282 to battery.

relay 203, back contact and locking device controlled by the armature of the line relay 281, which is now normai the switching relay 280 only partiallyattracts its armatures, that is, enough to disconnect the line of the called substation A from its normal battery and ground connections in the line switch C. ing, locks itself to circuit for t-he'relay 20-0 at armature 238, and at armatures and 239 reverses the connections ofthe line relay 201 with regard to'the trunk conductors 191 and 1941; As the current flow is now reversed in the up per winding of the electro polarized relay 103 in-the transmission repeater E which is included int-he circuit of the line relay 201, Relay 103, upon energizing, establishes a locking circuit for e 120, at armatures 122 and 123 reverses co; iections of. the line relay 151 of the first selector F with re 'ard to the trunk conductors and T1, and at armature 122 connects the alternating current relay 10% across the trunk conductors 70 and 71. The normal current flow over the conductors 70 and 71 being no reversed, the polarized relay 4 1 in'the repeater D is energized, Re.- lay 1%, upon operating, completes thecir cu-it of the relay 13. Relay .43, upon operating, establishes a locking circuit for itself at armature :56, at armature 55 places an additional ground upon the conductor which extendsto the visual signals 30 and v 203 and 280 are energized over this, Cll'ClLo. However, due to a mechanical interllclay 203, upon energiz ground on release trunk conductor 193 at armature 23!, prepares a test wiper 271, test contact 31 and at armatures 54 and 58 short circuits the condensers which are normally included in the trunk conductors 70 and 71, at the same time. removing the polarized relay 14 from in bridge across these 1 conductors.

The condensers in thetrunk conductors 7 0 'supervisory lamp L at itsarmature 25.

By the operation of this signal, the toll operator is notified that connection has been established with the desired line.

, Returning now to the operation of the electropolarized relay 103 in the repeater E,

another result of its energization is that the circuit of the line relay 201 of the connector H is opened at armature 121 and at the trontcontact of this armature and the front contact of armature 12-3 the battery feed r lay 102 is connected to the conductors 191 and 19% inorder to supply talking battery to the called subscriber when he answers. It will be seen that ground through the upper winding of relay 102, stands against ground through the line relay 201 and the battery through the lower winding of relay 102 stands against battery through the line relay 201; hence relay 201 willdeenergize. The line relay 201, upon deenergizing, completes the circuit of the relay 200. Relay 200, upon energizing, disconnects the line relay 201 from the trunk conductors 191 and 194: at armatures 215 and 219 thereby providing a direct metallic circuit to the called line from the repeating coil It in the repeater E, and at armature 21G opens the original energizing circuit otthe ring cut off relay 208.

The next operation is to ring the subscriber at substation A. For this purpose the toll operator momentarily operates her ringing key K thereby projecting ringing current out on the trunk line comprising conductors and 71 which-operates the alternating current relay 104 in the repeater E over a circuit extending from the free pole of the generator G by way of normally closed springs of key KP, normally closed springs of key K working contact and spring 27 of key K, ring of the plug, P, ring of thejack J, armature 54 and its front contact, conductor 70, upper left hand coil R, trunk conductor 71, front contact and armature 58, tip of the-jack J, tip ofthe plug P, spring 28 ofkey IQ and its working contact to ground A second path extends through the high resistance relay 100 to ground by way of armature 116 and its back contact, and the third path extends by way of armature 131 and its back contact, through the resistance 139,-armature 115 and its back contact, through the lower winding of the line relay 151 of the first selector F to ground. The relay 100 is of very high resistance and will not be operated by this ringing current. The alternating current flowing through the lower winding of the line relay 151 of the first selector F has no.

effect on it as a circuit for its upper winding is completed from ground at the workingvcontact of spring 28 of key K in the cord circuit 0. The alternating current relay 10a is operated over the previously traced ringing circuit and, upon attracting its armature 129, completes the circuit of the relay 101. Relay 101, upon energizing, removes ground from the ringing control conductor 192 at armature 111. This'operation opens the locking circuit of the ring out oif relay 208 in the connector H. The latter relay, upon deenergizing, completes the ring ng circuit of the called subscriber. The subscriber at substation A Wlll now be intermittently signalled until he responds.

\Vhen the receiver is removed at the called substation the ring out off relay 208 is energizedover the called subscribers line loop opens the ringing circuit and at the front contacts of these armatures finally completes the talking connection. Talkingbattery is now supplied to the transmitter at substation A from the windings of the battery feed relay 102 in the repeater E. This circuit will not be traced in detail but it will be observed that the lower line conductor extends uninterruptedly back through the connector H and the selector F to the lower right hand'winding of the repeating coil R and then through the lower winding of the battery feed relay 102 to battery, while the upper line conductor 191 extends back through the connector H and the selector F to the upper right hand winding of the re p-eating coil R from which point it may be traced through the said winding and through the upper windingof the relay 102 to ground. Relay 102 is energized by'the current flow over the called line loop and, upon attracting its armature 114, places an additional ground upon the ringing control conductor 192. Another result of the energization of relay 102 is that the high resistance relay 100 is placed in bridge of the trunk conductors 70 and 71. This bridge may be traced .from trunk conductor 70, up-

per left hand winding of the repeating coil R front contact and armature 122 windin 7 D of the high resistance relay 100, armature 116 and its front contact, resistance 125, armature 123 and its front contact, lower left hand winding of the repeating coil R- to trunk conductor 71. A further result of the energization of relay 102 is that the line rclay 151 is disconnected from the trunk conductors 7 0 and 71 and a local circuit is com pleted for it, which extends from ground through the lower winding of relay 151,'re sistance 136, armature 117 and its front con tact, back contact and armature 173, and thence through the upper winding of the line relay 151 to battery. The line relay 151 having been disconnected from the trunk conductors and 71 no battery will be present thereon and there will be no circuit for the relay 14 in the operators cord circuit. Relay 11 will therefore deenergize and eiface the supervisory lamp L.

The operator wiil now come in on the line by throwing the listening key K and, after observing that the proper person is at the telephone, will request the called party to deposit the coin or coins to pay for the con nection. When the coins are deposited, the operator is given an audible signal over the telephone circuit in the usual manner so that she will know that the correct amount has been deposited, and the polarized mag-- net of the paystation apparatus is also connected to the line in orderthat the operator may thereafter either collect or refund the deposited coins.

Everything is now in readiness for the conversation to begin, at least so far as con nection to the subscriber at substation A is concerned. Assuming that the desired party has been obtained n the distant ex change the operator will now complete the connection at her cord circuit and the connected parties can converse as desired. it will be observed that the connection includes the two conductor trunk line from the toll switching station to the main or local er:- change (the trunk comprising conductors 70 and 71) which is a decided economy over former arrangements which sometimes require three or four conductor trunk lines. Another advantage which may be pointed out is in the arrangement by which the called subscriber controls the release of the connection while his receiver is off through the medium of the relay 102 which controls the local circuit of the line relay 151 of the first selector F. This arrangement makes it possible for the toll operator to change cord 7 circuits after the calledparty has answered without releasing the established connection.

When the conversation is terminated both subscribers will replace their receivers. Upon the replacement of the receiver at sul station A the relay 102 in the repeater E is deenergized and the line relay 151 is again connected to the trunk conductors-70 and 7'1. As a result, the supervisory relay 1 1 in the operators cord circuit is energized and the supervisory lamp L is lighted to give the operator a disconnect signal. Before'releasing the connection the operator will have to collect whatever coins were deposited and tiis operation will now be explained.

In order to collect the deposited coins the operator will throw the collect master key K and operate the ringing key K in the cord circuit 0. The keys K and K are common to all the cord circu ts at the operators position and, when thrown, serve to connect either of the high voltage batteries B or B to the generator leads extending to the various ringing keys in the cord circuits. By the operation of the ringing key K the high voltage battery Bis connected to the trunk conductor 70 from whence it flows through the upper left hand winding of the repeating coil R, front Contact and armature 122, through the winding of the high resistance relay to ground by way of armature 116 and its back contact. The relay 100 is operated by the high voltage current from the battery 13 and, upon energizing closes the circuit of the slow acting relay at its armature 110. Relay 1053, upon energizing, completes a local circuit for the upper winding of the line relay 151 at armature 133 so as to maintain the selector F and connector H in their operated positions, connects the trunk conductor 70 direct to the trunk conductors 191 and 191- by way of the armaturcs 131, 130 and 134, over the talking conductors and wipers of the selector F and at the same time connects the conductors 191 and 191 to ground by Way of the resistance 1410 and the condenser at armature 132. Current now flows from the battery B, through the low resistance relay 32, springs of key K working contact of spring 27 and the said spring, ring of plug P, ring of jack J, conductor 70, front contact and armature 131, front contact and armature 130, armature 1G0 and its front Contact, front contact and armature 165, wiper 183, bank contact 187, conductor 191, front contact and armature 257, armature 239 and its front contact, armature 219 and its front contact, wiper 273, bank contact 277 and thence througlrthe polarized magnet at the subscribers substation to ground. ihe current from the battery 13 flows in the circuit of the polarized magnet in the proper direction to operate it to collect the deposited coin or coins, the paystation mechanism being reset at the same time.

When the circuit through the polarized magnet is established the resulting current flow is sufiicient to operate the relay 32 in series with the battery lead from the battery B and this relay, upon operating,closes the circuit of the supervisory lamp L thereby advising the operator that the collect circuits are operating and that the coins have been collected. The supervisory lamp L is common to all the cord circuits at the position and notifies the operator of the success fulcollection or refunding of coins. It should be observed, however, that the relay 32 is marginal an d does not operate in series with the high resistance relay 100. The

lamp will therefore be lighted only during collecting or refunding the deposited coins.

hile it is true thatthe alternating current relay 104 will energize momentarily due to the charging of the condenser 15%) the momentary operation of the armature 129 will have no effect as the relay 105 operates at once and ground is removed from the armature 129. I

In order to assure herself that the coins have been collected at the subscribers substation apparatus the toll operator will opcrate the key K twice. If everything is functioning properly the coins at the substation will be collected upon the first operation of the key'K and, upon the restoration of the key to normal, the polarized magnet at the substation will be disconnected from the line. When the key K is again operated there will be no circuit for the relay 32 and consequently the-lamp L will not be lit. As

. this signal does not operate the toll operator wi'. l know that the coins deposited have been collected and she will. restore her ringing key to normal and also the master collect control key K If the toll operator desires to refund the deposited coin rather than collect it she may do so by operating the master refund key K and then her ringing key K Assuming that the san'le connection exists as in the previous case where the operator collected the coins, if themastcr refund key K is oper ated the battery lead from the battery B is connected to theconductor 70. This is a high vo tage battery the same as the battery B but it supplies current of the opposite polarity and it follows therefore that the polarized magnet at the substation A will be operated in the opposite direction to refund the deposited coins rather than collect them. Except as pointed out the refunding operation is the same as the collecting operation and the operator is given supervision by means'of the lamp L in the same manner as was before described.

Under certain conditions the toll operator may find it desirable to collect or refund deposited coins at substation'A before she connects thetwo parties together for conversation. She may desire to refund the deposited coins in order to assure herself by a repetition of the usual audible signal when the coins are placed in the coin box that the proper amount has been deposited. This op eration will now be briefly described. The receiver at substation A being off the switchhook thebattery feed relay 102 in the repeater E will be energized and the high resistance relay 100 will be placed in bridge of the trunk conductors 7 O and 71. Now when the toll operator goes. through the regular operation of refunding by operating the ringing key in the cord circuit together with the refund master key K the high resistance relay 100 .is energized over the two trunk conductors and 71 in series- As a result of the operation of relay 100 a circuit is com pleted for the slow acting relay 105 and the refunding operation from this point on takes place in the same manner as was before described The release of the main connection over the toll service trunk is brought about by the removal of the plug P from the jack J, at least this is true if the called subscriber has replaced his recelver. In order to explain this more fully it will be assumed that'the plug is removed from the ack J before the subscriber at substation A has hung up. By film-removal ofithe plug P, the circuit of the line relay 42 of the repeater D is opened and this relay will deenergize but the relay 43 remains locked up. The busy visual signals 30 and 31 are thus maintained operated to indicate that the trunk is busy. Now, when the called subscriber replaces his receiver, the relay 102 in the repeater-E is deenergized and the line relay 151 of the toll selector F is connected across the incoming trunk conductors 70 and 71,-as was explained hercinbefore in connection with the control ofthe supervision. The effect of this is to energize the slow acting relay 41 which was placed in a bridge across the trunk conductors 70 and 71 by the deenergization of the slow acting relay 45, the latter'relay having deenergized shortly afterthe deenergization ofthe line relay Relay 4-1, upon energizing, opens 'the locking circuit of the relay 43. Relay 43, upon deenergizing opens the circuit.

in the connector H to deenergize.- Relay 155 is energized, in multiple with the release magnet 181 and is'therefore operated during the restoration. of the switch. Relay 155 opens a point in the circuit of the upper winding of the. line relay 151 at armature 1.73, and at armature 174E opens a point in the locking circuit of the relay 154: so as to prevent the relay i energizing and locking should the test wiper 185 encounter any grounded test contacts during the release of the switch. At the connector I-I, relay 203 upon deenergizing, opens the circuit of the relay 200. The latter relay, upon retracting its armature 217, closes the circuit of the release magnet 261. In this manner the connector H is restored to normal. .Upon the selector F releasing the relay 103 is deenergized as the circuit of its locking winding, which has been maintaining the relay armatures attracted after having been operated by the reversal of battery from the connector H, is opened at the off normal springs 171 of the selector F. In this manner all the apparatus used in the connection is restored to normal Returning now to the operation of the connector H when engagement was made with the bank contacts associated with the line of the substation A it will now be assumed that this line was busy. Under these conditions, there will be a; ground potential present upon the test contact 275 engaged by the test wiper 2.71. A circuit will thereby be. completed for the test relay 205. Re lay 205, upon energizing, prepares a locking circuit for itself at armature 2&6 to ground on the said test contact which is effective immediately following the deenergization of the slow acting relay 206, and at armature 2&8 places the busy tone from the busy machine on the upper heavy talking c011 ductor 191.

Having called the digits corresponding to the called subscribers number the toll operator will restore her key K to normal. As the supervisory lamp L" is not lighted at this time the toll operator will operate her listening key K in order to ascertain whether or not the desired line is busy.

The busy tone which was placed upon the upper heavy talking conductor is now audible to the toll operator and she will restore her listening key to normal and busy herself with other connect-ions while waiting for the dcsi-rec line to become idle.

lVhcn the line of the substation A be comes idle, ground will be removed from the test contact 275 and the test relay 205 will be deenergized to remove the tone from the upper heavy talking conductor and at the same time complete the circuit of the switching relay 203. Relay 203' will be energized as before described and will operate to reverse the battery over the incoming trunk line. By this operation the electropolarized relay 103 in the repeater E is energized and operates in the usual manner to establish a locking circuit for itself and to prepare a circuit for the battery feed. relay 102. An-

other result of the energization of' relay 103 is that battery is reversed over the conductors and 71 in the usual manner and the polarized relay in the repeater D operated to short circuit the condensers normally included. in these trunk conductors. By this operation the bridged supervisory relay 14 in the operating cord circuit is energized to light the supervisory lamp L, thus n0tifying the toll operator that the desired line has become idle. In the connector H the relay 200 is energized and a metallic circuit provided back to therepeating coil R. The operator at the toll board noting the operation of the lamp L will now operate her ringing key and the called line will be signalled before described-.. When the called party responds the battery feed re- 102 will be energized over the called line loop and operate to disconnect the line relay 151 from the trunk conductors 70' and 71. This latter operation causes the supervisory lamp L in the opera-tors cord circuit to be extinguished and she will be notified that the connection is completed. The subsequent operations in which the connection is finally completed, the coins collected or refunded, as the case may be, and the connection finally released, will take place in the same manner as was hereinbefore described.

'lhe above is the normal operation of the connector H when engagement is made with a busy line if this line is a private line. However, should the line of the substation A be one of a group of lines the test contacts 275 and 276 thereof will be connected in the manner shown in Fig. l. Fig. 4 represents a level of bank contacts having private lines and grouped lines, the lines of the group being fourtln. fifth, sixth, and seventh bank contacts. 'lhese lines are all listed under one umber in the directory and when connection is desired with one of these lines the connector If is rotated into engagement with the first line of the group. If this is busy and if there is an idle line in the group the connector H will operate to automatically select it. However, if all lines in the group arebusy the connector will remain with its wipers in engagement with the fourth set of bank contacts transmitting a busy signal to the calling subscriber until one of the lines becomes idle. VJhen this occurs the connector will then operate as previously niei'itioned, This operation of the connector H will now be described. For this purpose it will be a. sumed that the line of the substation A is the first one of the group of lines and is busy when the connector H is rotated into engagement with the bank contacts 2'. l-277, inclusive. As there is a ground potential present upon the test contact 275, the test relay 205 will be energized. As the test contacts 275' and mature 249 and its front contact, through the winding of the stepping relay 204 and thence through the winding of the slow acting relay 207 to battery. Relay 204, upon energizing, establishes a locking circuit for itself at armature 240 and at armature 241 completes a circuit for the rotary magnet 260. .R-otary' magnet 260 operates to rotate the switch wipers 270-273, inclusive, into engagement with the next set of bank contacts and also to open the looking circuit of the stepping relay 204 which dee-nergizes opening the circuit of the rotary magnet which deenergizes also. If this next line is busy the test relay 205 will be maintained energized and the stepping relay will operate, as before described, to complete the circuit of the rotary magnet and the switch wipers will be rotated into engagement with the next set of bank contacts. lVhen the switch wipers 270-273, are rotated into engagement with a set of bank contacts which are idle there will be no circuit for the test relay 205. Then, following the deenergization of the slow acting relay 205, the switching relay 203 will be energized and the same operations that have been described before will ensue. v

The relays 300303, inclusive, are associated with the test contacts of the various lines of the group and are in multiple with the private normal conductors extending from each test contact. line becomes busy the associated relay will be energized and, when all the trunks of a group become busy the connection between 5 the test contacts associated with the first line of the group will be opened and should the switch wipers of the connector H be rotated into engagement with the first set of bank cont-acts of a group of lines under these conditions the connector would operate in the same manner as if engagement As soon as were made with a private line. one of the lines of a group become idle the associated relay such as relay 301 would de energize and complete the connection of the two test contacts 275 and 276. The connector would then rotate into engagement with the idle line, all the foregoing operations taking place in the usual manner.

It is the usual practice in automatic telephone systems to take. the trunk lines which extend to the private branch exchanges from the bank contacts accessible to rotar connector switches. The toll connector has access to certain of, these trunk lines and Therefore, as each should the toll operator desire to connect with a subscriber in a private branch exchange she will operate her calling device in accordance with the digits of the number assigned to the trunk line extending to the desired private branch exchange. In re sp'onse to the operations of the calling device the connection would be set up 'in the same manner as was described hereinbefore and it will be assumed that the switches D, E, F and H are. the ones selected for use in extending the connection to the desired private branch exchange trunk line. When the connector H is operated into engagement with the first trunk line going to the branch exchange, if this trunk is busy the connector will automatically operate to select an idle one of the group of trunk lines. Upon being rotated into engagement with an idle trunk the switching relay 203 will be energized and will operate to reverse the battery back over the trunk line comprising conductors 191 and 194 and the electro polarized relay 103 in the toll transmission repeater E will be operated. Relay 103, upon operating, reverses the battery over the toll servicetrunk whereby the polarized re-.

lay 44 in the repeater D is operated, as is the supervisory control relay 14 inthe operators cord circuit. Relay 14 energizes to light the supervisory lamp L thereby notie fyingthe toll operator that the connection has been completed. The above operations take place in the same manner as was before described; however, the trunk lines going to the branch exchange are usually provided with a bridged signal across the trunk. This being the case, the battery feed relay 102 in the repeater E will be immediately energized over the connected trunk line and, upon operating, will complete a local circuit for the line relay 151 of the toll first selector F and place an additional groundon the ringing control conductor 192. In addition, by the. operation of relay 102 battery is removed from the toll service trunk comprising conductors and 71 and the bridged supervisory relay 14 in the operators cord circuit is deenergized to extinguish the supervisory lamp L. Ordinarily the efiace ment of this lamp serves to notif the operator that the called subscriber has answered. However, the operator will remember that she has called a private branch exchange and she will then operate the ring- .ing'key K in the same manner as if she upon energizing, removes ground from the ringing control conductor 192, at itsarmature 111 but this is inefiective to open the circuit of the ring out 01f relay. 208 in the connector H as the ringing control con- 102; A further resultof the energization of relay'101 is that "the right hand windings of the repeating coil R are disconnected from the trunk conductors extending to the connector at armatures 111 and 112 and the battery feed relay 102 would deenergize were it not for the fact that there isa local circuit completed for it whichextends from ground by way of front contact and armature 114, through resistance 137, front contact and armature 113, through the lower right hand winding of the repeating coil R, armature 12% and its front contact, and thence through the lower winding of the relay 102 to battery. As the relays 101 and 102 are now both energized ringing current from the generator G is connected to the trunk line extending to the private branch exchange in. order to operate the bridged ring down signal there-at, The subsequent operations wherein the connection is completed to the desired calledsubscriber in the private branch cxchai the conversation completed, and the connection released will take place in the usual manner andne'ed not be described herein.

Having fully described and ascertained the features of theinvention what is con-- sidered to be new and desired to have protected by Letters Patent will be pointed out in the appended claims.

that I claim is:

1. In a telephone system; a toll board and a local exchange, two conductor trims; lines extending from said toll board to said exchange, cord circuits at the toll board and automatic switches at the exchange whereby toll lines and subscribers lines may be connected oversaid trunk lines, paystation equipment at the stations on the subscribers lines, a source of direct current in said cord circuits, and means whereby the toll operator can connect one or the other pole of said current in circuit with the called subscribers paystation equipmentto cause the same to collect or refund deposited coins over said trunlrlines.

2fln a telephone system, a toll linetermii'iati'ngijat a toll switching operators position, ainautomatic exchange, a two-conductor' trunk line comprising two induc- Livelyconnected sections extending from said POSltlOlT'tO said exchange, a subscriber's line at'said automatic exchange, autoinatic switches controlled over said trunk line by a toll operator for setting up a con necti'o'n between said toll-line and said subseribefis iline, paystationmechanism at the subseribefis station, and means controlled by' the -toll:operator for completing a direct connection 1 between the two sections of said tlllnlii line for :"eollecting or refunding depositedicoins. w n l 3. 1n a telephone system, a toll line terminating at a toll switching operators position an automatic exchange, a trunk line extend a subscribers telephone line, means comprising an operators cord circuit and a system ottoll service trunks for connecting said lines, means including a paystation mechanism at the sta ion on said telephone line, and means whereby the operator can control the collection and refunding of coins deposited in said mechanism to pay for the :nec-t'on orer adirect current path inthe two sides otone of said toll service trunks in. series.

5; in a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection extending from said switchboard to said line, said connection comprisinn, two inductively connected sections, pa station mechanism at the station on said line, and means whereby the toll operator can conduetivcly unit said sect-ions torthe purpose of controlling said paystation mechanism.

(5. in a telephone system, a toll opera tors switchboard, a subscribefis line, automatic switches controlled by the toll operator to establish a connection extending "from said switchboard to said line, said connection comprising two inductively connected sections, paystation mechanism at the station on saidline, and means whereby the toll operator can control said paystation 1necha nisni to collect or retund'deposited coins, the control in each instance being exercised partly over a directcurrent circuit including the two sides of the first of said sections in series and partly over a branch circuit in cluding the two sides of the second of said. sections in parallel T a telephone system, a toll opera- 4. Jill tor's switchboard, a subscribers line, automatic switches controlled by the toll opera tor to establish a talking connection extending from said switchboard to said line, said connection comprising two inductively con nectedsections,paystation mechanism at the station on-said line, and means whereby the toll operator can control said paystation mechanism either before or aiter' the called subscriber has -replaced his receiver, the united control being exercised in theffirst instance-ever a circuit including the 'two sides of the first of said sections in series,

' sources of high voltage current of opposite polarities, means at the said switchboard for connecting either of said sources in series with the two talking conductors of the first of said sections, and means responsive to the high voltage current for connecting the series circuit with both talking conductors of the second of said sections in order to control said paystat on mechanism.

9. In a telephone system, a toll operatorsswitchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection between said switchboard and said line, said connection comprising two inductively connected .sections, paystation mechanism at the station on said line, sources of high voltage current of opposite polarities, means at the switchboard for causing a flow of current from one of said sources over the two talking conductors ot the first of said sections in series, and means responsive to current flow in the series circuit for causing a current fiowjrom the same one of said sources over the two talking conductors of the second of saidsections in parallel in order to control said paystation mechanism.

10. In a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection between said switchboard and said line, said connection com-. prising two inductively connected sections, paystation mechanism at the station on said line, sources of high voltage current of opposite polarities, means at the switchboard for connecting one of said sources with a talkingconductor of the first of said sections, and means responsive to the resulting current flow over said conductor for connecting the same with a conductor of the'second of said sections, whereby a flow of current is set up over said last named conductor to control said paystation mechanism.

11. In a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection between said switchboard and said line, said connection com prising two inductively connected sections, paystation mechanism at the station on said line, sources of high Volta e current of oppo-- site polarities, means at t e switchboard for connecting one of said sources with a talking parallel to control said paystation mechanism. i

12. In a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection between said switchboard and said line, said connection comprising two inductively connected sections, paystation mechanism at the station on said line sources of high voltage current of opposite polarities, and operator controlled means for collecting a coin deposited to pay for the connection, said means comprising a device for connecting one of said sources with a talking conductor of the first of said sections, and means at the unction of said sec tions responsive to current flow over the said conductor for conductively connecting said sections together, whereby a flow of current is established over a talking conductor of the second of said sections to control said paystation mechanism. I g

13. In a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a connection bet-ween said switchboard and said line, said connection comprising two inductively connected sections, paystation mechanism at the station on said line, sources of high voltage current of opposite polarities, means at the switchboard for connecting one of said sources with a talking conductor of the first of said sections, means responsive to the resulting current flow over said conductor for connecting the same with a conductor of the second of said sections, whereby a flow of current is set up over said last named conductor to control said paystation mechanism, a line relay in one of said switches controlling the release of the connection, said relay being normally energized over the two talking conductors of the first of said sections in series, and means for closing an alternative local circuit for said line relay while the high voltage current is on the line.

14. In a telephone system, a toll operators switchboard, a. subscribers line, paystation mechanism at the station on said line, a toll service trunking system includ ing selector and connector switches, means whereby the operator can control certain of said switches to establish a talking connection between said switchboard and said subscribers line, a repeating coil dividing the talking circuit into two inductively connected sections, sources of high voltage current of opposite polarities, a key at the switchboard ill 15. in a telephone system, an operators switchboa d, nlurahtyof cord circuits for use in ostablii connections, a r;

key in each cord circuit, a. ringing current generator norn'ially connected over a common conductor to all of said ringing keys, two sources of high voltage current for u in controlling paystation mechanism, and two master keys serially connected in th: common conductor so that operating l proper master key either elf said 'irces be substituted for said generator, thus enabling the operator to connect either oil said sources across the strands of one of her cord circuits by way of the associated ing key.

v16. In a telephone system, the combination of subscribers lines, an operators position, means including toll switching trunks and automatic switches for extending a, call from said position to subscribefis line, a coin box at the substation of said line hav ing a coin disposal magnet, collect and re fund current sources at said position, a coin current apg ilying relay, :1- manual switch at said position for applying one of said cur rent sources to said relay to cause the same apply this same current source to the con nected substation to operate the coin disposal magnet in one manner, and a manual switch at said position for applying said other source of current to said relay .to cause the same to apply this latter current source to operate the coin disposal magnet in another manner.

17. in a telephone system, an operators switchboarcha plurality of cord circuits for use in establishing connections, a ringing key in each cord circuit. a source of ringing cuii'int normally connected over a common cord. ctor to all of said ringing keys, two sources of high voltage current for use in controlling paystation mechanism, and.

means for enabling the operator at said switchboard to connect either of said sources across the strands of her cord circuit by way at tie associated ringing key.

18. In a telephone system, a toll operators switchboard, a subscribers line, automatic switches controlled by the toll operator to establish a talking connect-ion extendig from Said switchboard to said line, said connection including a trunk line having but two conductors extending between the said automatic switches and said switch- Ll con arising two inductively connected tions, p'aystation mechanism at the station on said line, and means whereby the toll operator can control said paystation mechan sm to collect or refund deposited coins over a circuit including only one and the same -'-e of the first section anti 'round return.

if). ln a telephone system, a calling and a called station, a connection between said stations comprising two inductively connected sections, a call charging device at one of sale, stations, and means controlled by said other station for momentarily uniting said crating said device.

20. in a telephone system, a first and a d station, a talking connection extends tween said stations and comprising .uctively connected sections, a call device at said second station, and means controlled by said first station either before or after the receiver is replaced at said second station for uniting said sections conductively for the purpose of operating said device.

21. ln a te ephone system, a calling and :1 called. station, a talking connection extendiiy between said stations comprising two inductively connected sections, a call charging device at said called station, a source of current, neans controlled by said calling station for connecting said current source to tie talking conductors of said first section in a series circuit, and means responsive thereto for connectingsaid current source to he talking conductors of said second section in a parallel circuit for the purpose of selectively controlling said device.

In witness whereof, I hereunto subscribe my name this 27th day of June, A. ll, 1921.

JOHN VVICKS.

-one; eonductively for the purpose of op- 

